@mixin hide-line($line) {
    @extend %hide-line;
    -webkit-line-clamp: $line;
}

//高度随宽度成比例变化
@mixin ratio($width,$height) {
    position: relative;
    width: 100%;
    display: inline-block; //必须为inline-block
    vertical-align: middle;
    &:before {
        content: '';
        display: block;
        margin-top: ($height/$width)*100%;
    }
    > * {
        position: absolute;
        top: 0;
        bottom: 0;
        left: 0;
        right: 0;
    }
}

//角标
@mixin mark($width:5,$color:transparent) {
    @extend %mark;
    border: {
        top: ($width+px) solid $color;
        right: ($width+px) solid $color;
        bottom: ($width+px) solid transparent;
        left: ($width+px) solid transparent;
    }
}